Airway smooth muscle cell proliferation increased in asthmatics Scientists have shown, in vitro, that airway smooth muscle (ASM) cells from patients with asthma undergo increased proliferation compared to those taken from non-asthmatic patients. Increased ASM within the bronchial walls of asthmatic patients has been well documented. A team of Australian researchers at the University of Sydney asthma management about asthma investigated whether asthmatic cells exhibit a different pattern of proliferation from that of cells obtained from non-asthmatic patients. Human ASM cells were obtained from 10 non-asthmatic and 12 asthmatic patients. These cells were then cultured for seven days. Over the seven-day period, the cultures were analysed for cell counts, titrated thymidine incorporation and cell cycle. The number of ASM cells asthma attack cause about asthma in the asthmatic samples were significantly higher at days three, five and seven than those taken cultured from non-asthmatic patients. Titrated thymidine incorporation was increased 3.2-fold in asthmatic cells compared with non-asthmatic cells within the first 24 hours. Furthermore, cell cycle analyses revealed that a significantly greater percentage of asthmatic ASM cells were in the G2+M phase - when chromosomes about asthma about asthma separate and cytoplasmic division occurs. The researchers said that care must be taken when extrapolating from the results of cell culture to in vivo conditions, but said their results indicated that an inherent abnormality of the ASM proliferation existed and that this might also be the case in vivo. Source: Johnson et al, Respiratory and Critical Care asthma pediatric treatment about asthma Medicine 2001; 164:474-477
